Ludwig von orth



"(No Model.)

' L. VON 'ORTH. APPARATUS FOR SYNGHRONIZING CLOCKS.

No. 466,518. o} Patented Jan. 5, 1892.

INVENTUR. Luamq vow O-rtm UNITED STATES PATENT OFFIC LUDWIG Von ORTH, or BERLIN, GERMANY.

APPARATUS FOR SYNCHRONIZING CLOCKS.

SPECIFICATION forming part of Letters Patent No. 466,518, dated January 5, 1892. Application filed January 23, 1891- Serial No- 3'78,797. (No model.)

To all whom it may concern:

Be it known that I, LUDWIG-VON'ORTH, a sub ect 0f the King of iirtemberg, residing at Berlin, Prussia, Germany, have invented new and useful Improvements in Apparatus for Synchronizing Clocks, of which the following is a specification.

My invention has reference to improvements in means for synchronizing clocks when interpolated in a net-work of electric wires, such as telephone, telegraph, firealarm, or other wires; and it consists in certain novel features in the construction and arrangement of the several parts, whereby a larger number of secondary or subscribers clocks can be synchronized by the masterclock or equivalent means than heretofore while the apparatus at the central office is much less complicated, all of which is fully pointed out in the following specification and claims and illustrated in the accompanying drawings, in.whicl1- Figure 1 is a diagram illustrating the general arrangement of the several devices and circuits when the clocks are interpolated in a telephone system. Figs. 2 and 3 are respectively front and rear views of a form of secondary clock which may be used, the dial in Fig. 2 being omitted.

Similar letters indicate corresponding parts throughout the several views.

In the drawings, referring at present to Fig. 1, the letter S designates the switchboard or equivalent connection at the central oflice.

C is the master-clock at the central office; C, the secondary clock at one of the subscribers offices, and'T the subscribers telephone.

Numeral 10 designates one of the subscrib= ers lines, and 11 the ground-line at the cen tral office common to all the subscribers lines.

The master-clock O is provided with a circuit-closer a b, operated automatically by the clock in a'well-known manner to close the circuit of the main or clock battery B at certain predetermined intervals-say once a day at twelve oclock midnight. One wire 12 from the battery is connected with the groundline 11 atthe point V thereof and includes the circuit-closer a Z). The other wire 13 is con- .spring K, connecting with the line 10 to the telephone T, and a third contact-spring L, connecting by wire 14 to a relay D. The contact-spring J is arranged to play between the contact-springs K and L, to close the circuit through either the wire 10, leading to the telephone, or through the relay D. Any I suitable well-known means may be employed 7c for automatically operating the switch. For instance, as shown in Fig. 3, the secondary clock movement is provided with a disk H, upon which rides a roller-stud 2'", carried by the contact-spring J, said disk having a recess or notch h on its circumference. Vhen the roller-stud rides on the circumference of the disk, the contact-spring J is held in contact with spring K; but when the stud enters the recess or notch h spring J engages contactspring L. The arrival of the recess or notch under the roller-stud is so timed that a short time before the master-clock O closes the circuit of battery B the spring J is brought into contact with spring L, thereby cutting the telephone T out of the circuit.

To set the hands of the secondary clock any suitable means may be used. For instance, as shown in Fig. 2, a hand-setting fork P, the arbor of which is actuated through a train of gears by the drive-weight of the clock, is caused to engage with a roller 0 on a crankarm 0, which is keyed to the arbor of the hour-hand, said fork having segmental ribs at the side next to the clock and a recess 72 for this purpose. Normally, the fork P is held out of action by a hooked lever m, secured to the armature of an electro-magnet M, which engages a notched stop-disk d, that is in gear with the said train of gears for driving the fork.

B designates a local olock-battery, one pole of which is connected byv wire 15 with the elect-ro-magnet M. The second wire 16 from the battery is led to a contact-sprint, n of a circuit-closer n 0, from the opposite contact 0 of which it is led to a local resistance R and from thence to the electromagnet' U. The relay D is connected by wires 17 and 18 with the circuit of battery B on opposite sides of the resistance and by wire 10 with the ground-wire of the subscribers telephone. The contact-spring a is connected with. and made to co-operate with the main switch of the secondary clock, so that when the circuit through the subscribers telephone is broken the circuit is closed by spring 0". through the local battery.

The operation of the apparatus is now as follows: Normally the circuit is established with the telephone by the switch of the secondary clock; but shortly before the synclironizing' period the said switch is automatically changed to cut the telephone out of the circuit, while at the same time circuit-closer n o closes the circuit of the local battery B, and a local circuit is established from battery B over wire 16, circuit-closer n 0, resistance It, electro-magnet M, and wire 15 back to the battery; but in view of the resistance offered by R the current will not affect the armature of the electro-rnagnet and the hand-setting device is not released. On the hour the master-clock G closes the circuit at a b and the current flows from battery B over wire 12 to the ground-line, where it is divided'into partial currents, the one flowing over wire 10, contacts .I L, wire 14, relay D, wire 19 to the ground, and the other current passes over resistance R. The current over wire 10 to the relay closes the circuit at said relay and the current from the local battery B now passes over wire 16, circuit-closer n 0, wires 16 and 18 to the relay-contact, and from thence by wires 16 and 17 to electroqnagnet M and over wire 15 back to the battery, thereby shortcircuiting the resistance R, and the increased current now causes the synchronizing device to be released and set the hands.

By employing a main battery of suitable electro-motive force and properly fixing the resistance of coil R (which may be so small that it disappears entirely with respect to the resistance of the telephone system and cannot act prejudicially on the same) the current passing over the subscribers line will produce no effect upon the alarms of telephones of oiiices not having a clock, while the relays of the subscribers clocks being much more sensitive are thrown into action.

IVhat I claim as new, and desire to secure by Letters Patent, is

1. In combination with a telephone system or other network of wires, a master-clock at the central station provided with a circuitcloser, an auxiliary line, including said circuit-closer and a battery B, a resistance It, interpolated in the ground-wire of the central station to divide the current, as specified, and a series of secondary clocks, all so arranged that on the closing of the circuit of battery B by the master-clock divided circuits pass over all the telephone-subscribers wires and to the secondary clocks of the clock subscribers, substantially as and for the purpose set forth.

2. In combination with a telephone system or other net-work of wires, a circuit-closer at the central station, a resistance interpolated in the ground-line to divide the current from the battery, secondary clocks, each provided with a switch, a local battery, a relay, and a resistance, and electrical connections, substantially as described.

3. A secondary clock provided with a synchronizer, a switch, a relay, and a circuitcloser constructed to close the circuit through a local battery and an interposed resistance, substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

LUDWIG VON ORTII.

Witnesses:

EDWARD PEITZ, G. I-IiiLsMANN. 

